


Triptych

by Mad_Maudlin



Category: Stargate Atlantis, Stargate SG-1
Genre: Alternate Universe - Canon, Apocafic, Episode Related, Gen
Language: English
Status: Completed
Published: 2010-01-23
Updated: 2010-01-23
Packaged: 2017-10-06 14:51:24
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,779
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/54856
Author URL: https://archiveofourown.org/users/Mad_Maudlin/pseuds/Mad_Maudlin
Summary: <blockquote class="userstuff">
              <p>Matter can neither be created nor destroyed.</p>
            </blockquote>





	Triptych

**Author's Note:**

> A/N: Written for the [](http://www.livejournal.com/users/sga_flashfic/profile)[**sga_flashfic**](http://www.livejournal.com/users/sga_flashfic/) "Doppelganger" challenge. I was inspired for this almost as soon as I'd seen "Moebius," and that seemed like the perfect challenge for it. So assume BIG spoilers for that episode and small ones for SGA's first season.

2.

"You're saying you just _found_ it?"

John flinched at the hint of a squeal in McKay's voice, which was audible all the way down the narrow concrete corridor. Cheyenne Mountain was everything Atlantis wasn'tcramped, crowded, pale under the fluorescent lightsand he honestly just wanted to find some place to sleep until he found out his fate. Probably not a discharge, but certainly he wasn't ever getting near a Stargate again, much less one to Pegasus. He wanted to sleep until he could forget about Everett and Sumner, about Ford's family and his dead black eye, about last resorts and radioactive flowers opening to fill the sky. Sleep until he could forget the worst of the past year was anything but a freaky nightmareeven if that meant the best was just a daydream.

But until he was officially given the boot, he supposed it was still part of his job to keep McKay from getting shot. Especially by their own people.

John followed the sound of the argument to a lab cluttered with old books and pottery, where Rodneystill in the shabby suit he'd worn to debrief twenty-four hours agowas staring incredulously at Dr. Jackson and Lieutenant Colonel Carter, though his arms were braced on the edge of the table as if he were a few moments away from tipping over. "...left a video tape explaining what wethe other usdid," Jackson was explaining. "So, yes, in a sense we did just _find_ it, but"

"My god," Rodney said, scrubbing at his face, "I'm surrounded bylook, I knew you were an idiot, what with the soft sciences and all, but honestly, Sam, I'm completely disappointed in you here."

Jackson and Carter both scowled, and John decided this was the part where he saved Rodney from himself. "McKay," he called. "Didn't we have the talk about manners after the third time you almost got sacrificed to the Ancestors?"

Rodney waved him over with an eyeroll. "Major, just _listen_ to how they _think_ they acquired the ZPM they sent us. Just listen to this. It'sI can't even believelook, look at this" and he grabbed the nearest laptop, nearly sending some kind of religious icon to the floor in the process. Carter flinched, and Jackson snatched at the laptop's cables before they disturbed anything else; McKay, oblivious, started tapping away furiously.

John looked at Jackson and Carter for explanation, and they both sighed at him. "We were explaining," Jackson said, stacking up a couple of scrolls and settling them somewhere safe, "that the ZPM was recovered on an archaeological dig in Egypt. Apparently we, SG-1, went back in time five thousand years to steal it from Ra and hide it in a tomb that we knew would be excavated recently, along with a video-taped message from ourselves to ensure we didn't corrupt the timeline."

"You see? You see what I'm talking about?" Rodney said without looking up from the laptop.

John ignored him in favor of a slow whistle. "How'd you pull that off? The time-travel, I mean."

"We found an Ancient time machine," Carter explained. "It's built into one of those, the"

"Puddle jumpers," McKay said, "and I hope you're proud of yourself, Major, the name's stuck."

"'Cause it's a good name," John said, before turning back to Carter. "So you guys just jumped back in time and?"

"_We_ didn't," Jackson said quickly. "We meaning us. Because we found the ZPM we didn't...need...to find the ZPM. Um."

"By going back in time, we eliminated our own reason for going back in time," Carter added. "It's a temporal paradox."

"Wrong," McKay said.

Carter blinked at him and said, "Excuse me?" as he spun the laptop around to face the rest of them. "It's nearly a classic example of a paradox"

"Except there _is_ no such thing as a temporal paradox, which you would've known if you'd read any of the research we sent you in the databurst," Rodney said triumphantly.

Carter folded her arms and tilted her chin up. "McKay, you send over two hundred gigs of data and reports. We've barely had time to scratch the surface."

"Well, you should've paid attention to _this _if you or any of your alternate selves were planning to go screwing around in the past." Rodney pointed to the laptop screen again, and John craned his head until the words came clear. _Intertemporal Causality, Entropy and Quantum Collapse by Brendan Gaul, Ph.D._ "It's an incising and thoughtful analysis that I would certainly have come up with first if Major Hairdo here hadn't decided to put me in mortal peril on a regular basis for the good of the city," Rodney explained with a certain lack of rancor, "and it also concisely disproves the concept of the temporal paradox by substituting causal explanations across alternate realities."

"English, Rodney," John said.

Carter, already scrolling through the document, frowned. "I see what he's arguing," she said, "except we didn't alter the timelinewe left a video tape for ourselves to check the present against, just to be sure."

Rodney snorted. "And you think you captured every single detail of an entire universe in a few hours of video? For all we know, in the universe of origin there was a different, different president of _Brazil,_ or the open-source movement toppled Microsoft, or I'm allergic to peanuts." He paused. "God, that would be a depressing existence, wouldn't it?"

"Um, excuse me," Jackson said, "what are you talking about?"

McKay opened his mouth; Carter beat him to it. "According to Dr. Gaul's theory, time travel within one's own timeline isn't actually possiblethe moment you move into the past, a new alternate timeline splits off from that point to account for your presence. You can travel forward into this new timeline, but never into your original timeline"

"Except the quantum state variables would be identical, because, well, for reasons you people wouldn't be capable of understanding, but the important part is that there would never be any problems with entropic cascade, so time-travel resembles a viable way to jump between dimensions without the possibility of a slow, painful death as your molecules one by one slide out of phase," McKay said in a single breath. "Like Old Elizabeth, on Atlantis."

"Or _Back to the Future?"_ John offered.

"Major, if you mention that movie one more time"

"So, so you're saying," Jackson said, before McKay could get distracted, "you're saying that the SG-1 who made the tape, even though they're identical to us, are actually from an alternate universe?"

"More or less," Carter said.

"Exactly," Rodney said at the same time, then added, "They actually _created_ this universe the moment they activated the time-travel device, and so their actions in the past to steal the ZPM were always part of our timeline. If they _had_ tried to return to this present, they'd have run into their own doublesmeaning youwho never traveled back, and, well, that would be terribly awkward, wouldn't it?"

There was a pregnant pause, then Jackson asked quietly, "And in the original timeline? What happened after the other SG-1 left?"

"Who knows?" Rodney said with a careless little handwave. "I mean, they may not have even had an Atlantis expedition. It wasn't mentioned on the tape, was it? Or maybemaybe it's like Old Elizabeth's timeline and they never could've used the ZPM anyway. Or something."

"Something," Carter said a little weakly, frowning a little.

"Jack's pond has fish," Jackson said hopefully.

"Right," John said, as if that made sense; but he couldn't help a little shiver on the back of his neck. _Like someone just stepped on my grave._

1.

"Doctor McKay, we have to go!"

"Just one more minute!" _Good crystal, good crystal, they're all good crystals, the wiring is good, the ZPM is interfacing properly (no thanks to that ingrate Zelasky or whatever his name is supposed to be)  
_  
_"Doctor McKay!"  
_  
Rodney ducked as the entire cavern shivered, raining bits of ice down on his head through fissures in the ancient ceiling. It took precious seconds for him to remember how to breathe, and then he was up again, racing to the sleek alien chair and the laptop wired into its base. "I've almost got it!" he shouted, "come on, come on, come on, the idiots from the tape said you'd work"

But the idiots from the tape weren't _here_not the ones who'd made it and not their counterparts in this timeline, the ones who had taken his gateship and never returned. And now aliens in flying pyramids were raining down fire all over the Earth, and Hammond had told Rodney to make the weapons in Antarctica base workand there had to be weapons, because the tape said there were weapons, and Christ, was Rodney getting sick of the goddamn tape.

But he'd found the weapons, and he'd powered them (and _that_ wasn't with any help from the damn tape, thank you, that was pure unalloyed genius at work) and now if he could only establish an interface with the guidance systems

"Doctor McKay," the radio in his ear crackled, "we are evacuating this outpost! You are to report to NORAD for evacuation through the Stargate!"

He stared up at the ceiling, as if he could peer through a mile of glacier at the moron making the demand. "Excuse me?" he blurted. "You're just _giving up?"  
_  
"It's General Hammond's orders, Doctor."

"I just need another minute to configure the output parameters"

"We don't have another minute," a different voice barked over the radio. "So get up here or I'll come down there and haul your ass up myself."

"Thank you, airman, that's very mature of you," Rodney snapped. "But in case you hadn't noticed, I'm trying to _save_ _the_ _planet_ here"

The first voice cut him off. "Doctor McKay, there's nothing left to save."

Rodney ripped off his earpiece and threw it against the wall, then remembered to shut off the base unit as well. Idiots. All of them. He could do this. He was a goddamn genius. All he needed was a little more time

The entire cavern shuddered around him again, and he threw his arms over his head. Time, of course, was the one thing he was running short of.

He dragged a metal folding table onto the chair dais and sat under it, because bits of ice were now raining down constantly, and wouldn't it be rich if he managed to activate the weapons system just before the roof caved in entirely? But he was going to activate it, he wasn't just going to _give up,_ what were they thinking? Though if the evacuation helicopters didn't get themselves away soon, the alien ships above were going to kill them all anyway

"Doctor McKay?"

"Busy!" he blurted, slapping at his earpiece before he remembered it wasn't on. He peeked out from under the table to find a figure in a green flight suit stumbling through the room, slipping on the loose chunks of metal and ice. "Are you entirely _insane?"_

The pilot looked up and smirked at him. "Dr. McKay, I presume?"

"This entire place could come crashing down on us any minute," Rodney shouted, "and I am a very busy man who can't afford to be distracted right now!"

"I have orders to get you out of here," the pilot said, crawling the last yards at the cavern shook again. "So I'm getting you out."

"Yes, yes, you must be the Neanderthal I spoke with earlier," _conversion algorithm compiled, decompression algorithm compiled, so why doesn't this make a damn bit of sense? _"but as I said, I'm much too busy to deal with your savior complex while I am in the process of establishing our only line of defense against the vicious aliens that are trying to bring the entire ice shelf down on our heads"

The cavern rocked and the lights flickered; the pilot dove under Rodney's table just in time to duck a chunk of the ceiling the size of a bowling ball. "You really think you can fight those things off?" he asked skeptically, and tried to look over Rodney's shoulder. "I mean, have you _seen _them?"

Only on deep-space telescopes, and that was as much as Rodney wanted to see, thanks, because just running the Doppler analysis had scared him to the core. "I know I can fight them, if I can only make this weapon work, and will you quit breathing on my neck? It's not like you understand any of this anyway."

"Looks like a chair to me," the pilot said dubiously.

Rodney sighed, as more gibberish spilled over his screen. "It's meant to be some kind of neural interface, like the gateship controls, only the tape doesn't explain how it works, only that it's genetic, and nobody on our team has managed to make the thing so much as twitch, which is why I am bypassing it and why I am so _very very busy!"_

"What tape?"

Rodney decided to spare another few incredulous seconds of boggling. "You don't know about the tape?"

The pilot shrugged. "I know I flew a big ol' metal donut out of here a couple months ago hitched to my chopper, and now I'm supposed to get you out."

"Well, I'm not going," Rodney said, pounding away at another conversion routine, because the data had to make sense _somehow,_ no matter what Grodin said about parallel processing. "I'm almost done here and when I get it I'll be able to knock those things right out of the sky"

"I think it might already be too late for that, doc," the pilot said.

"Yes, well, it's also too late for us to leave with a reasonable chance of not getting shot down by their fighters, and yet you're still here, aren't you?" Rodney asked.

The pilot shrugged again. "I'm not really good at leaving people behind."

"Yes, well, if you going to be stuck here" The laptop screen fritzed and fuzzed, and Rodney swore as he jiggled a cable. "Look, make yourself useful and make sure all these cables are still attached to a crystal, I can't do anything if I'm not even plugged in."

The pilot clambered out from under their protective table and up the chair dais, following the cables through the layer of icy debris. The whole chamber rocked violently, and more far-too-large chunks of ice fell like bombs around them; the pilot rolled out of the way and pushed himself up against the chair, then up into it as a light fixture twisted free from its mount and gave way at his feet

And the chair lit up.

The contents of the laptop screen were still ninety percent gibberish, but the point was that the chair was _moving,_ spinning, glowing with a fierce blue light that made the pilot's tan face look strangely pale. "Did I do that?" he asked, fingers clenching over the contacts.

Rodney scrambled to his feet, only half-aware that the bombardment from above had stopped. "Listen. Listen, airman"

"Major," the pilot said.

"Whatever." Rodney placed his hands over the major's, and felt a new kind of warmth in the gelatinous touch pads. "Think of where we are on the planet."

Over their heads, a flickering hologram appeareda globe, showing their base and all the alien warships swirling around them, too many to ever count, and Rodney suddenly realized why Hammond had ordered a withdrawal, why they would think this battle hopeless

"So how do I bring the fuckers down?" the major asked.

"I...really have no idea," Rodney said.

"I thought you said"

"It's a neural interface!" he snapped. "Clap your hands and believe in ballistic missiles or something!"

The major squeezed his eyes shut in an expression that looked altogether too much like taking a shit. Rodney would've commented, but a moment later the floor of the chamber opened itself in a column of white light. On the hologram, one by one, the looming red triangles began to wink out.

0.

Jinto woke him long before dawn. "Major. Major Sheppard."

"G'way, Jinto."

"Major Sheppard, your people have come."

That had John upright immediately, clutching for his weapons. "My people? What people?"

"They used your radios," Jinto said. "They called themselves _Daedalus_ and they wish to speak to you."

John squeezed his eyes shut and breathed deeply. "You're certain?"

"I was with Aiden, preparing for the hunt."

"Anyone know where McKay is?"

Jinto flinched. "Aiden is looking for him."

Good. Ford wasn't the best guy to handle Rodney, but he could make the judgement call. "Go get your dad and Teyla," John said. "I'll meet you at the generator."

"Do youcan I"

"Go," John growled, and reached for his crutch.

He fumbled in the dark of his tent for clothes and struggled into them, then levered himself upright on the empty ammunition case that now served him as waterproof storage. At the last minute, he found his expedition jacketnow patched and lined with skins he'd cut and cleaned himselfand shrugged it over his shoulders. Winter was coming to the camp, and he might as well be warm.

By the time he'd gotten to the squat hut that housed their electrical equipmentthe Athosian's temperamental solar cell, a naquadah generator half-depleted, and an assortment of radios, weapons and tools left to chargeTeyla and Halling were already there. So was Ford, and so, surprisingly, was McKay, though he had a definite starboard list. Ford was talking into a radio. "...on his way. Like I said, it's barely daybreak here, we're looking for people."

_"What about Dr. Weir?"_ the voice in the radio said.

John balanced on his crutch and snatched the radio out of Ford's hand. "Dr. Weir is dead," he said. "Now who the hell are you?"

The voice on the other end of the radio seemed shocked for only a moment. _"This is Colonel Stephen Caldwell of the Earth ship _Daedalus. _To whom am I speaking now?"  
_  
"John Sheppard of the Atlantis expedition. Pleased to make your acquaintance."

There was a moment of dead air, then Caldwell returned. _"Major Sheppard, we were dispatched by Stargate Command to locate and rescue your expedition, and provide relief, if possible."_

John snorted. "You're a couple of years too late for that, Colonel."

Again, a moment of dead air. _"Major, perhaps we could have this discussion face to face,"_ Caldwell said slowly, as if he were talking to a crazy person. Which, John reflected, might not be as far off the mark as he'd like to think. _"We can transport down with some food and medical supplies."_

John carefully made eye contact with Teyla and Halling, who both nodded to him after a moment. Ford just shrugged, and McKaywell, who the hell knew what McKay was thinking anymore. He was leaning against a post, now, shivering in just a t-shirt, and he wouldn't meet anyone's eyes at all.

"All right," John said into the radio. "There's a landing strip on the south side of our camp. You should be able to see it when the sun comes up."

_"Agreed, Major. _Daedalus_ out."_

John looked around the little group again, then pushed himself straight on his crutch. "Ford, I want the landing strip under guard, Make sure all the jumpers are secure, too."

"You do not trust this Caldwell?" Halling asked.

"I don't think Caldwell trusts us," John shot back. "Can you round up the rest of the council? We might as well make this a formal event."

"Dr. Schwartz should also be present, to receive the medical supplies," Teyla said. "I will summon him."

Ford tossed off a saluteyou just couldn't take the Marine out of some peopleand trotted towards one cluster of tents; Teyla and Halling went towards another. The sky was looking pewtery in the west now, counting down the moments until their meeting. John was alone with McKay.

"Are you sober?" he asked right out.

McKay raised his chin and wobbled a little. "Yes."

"Do you want to come along?"

"What, to recount our glorious failures to the unblinking eye of the US Air Force?"

John had learned, by now, when not to take the bait with him. "We'll all have to talk to them eventually. It doesn't mean you have to talk to them now."

McKay looked away again, eyes going blank as his fingers started tapping restlessly against his forearm, complicated patterns like music. John waited patiently for him to snap out of it. "I need a coat," he finally mumbled.

"That might be a good idea, buddy." John didn't follow McKay's wobbly walk back to his tent; if he made it to the landing strip on time and under his own power, that would be proof he was fit to talk to strangers. If not, someone could herd him back to his tent to sleep it off without anybody from this _Daedalus_ seeing a thing.

By the time the sun broke the horizon, they had set up a cordon around the landing pad, of Lanteans and Athosians armed with Wraith stunners and the last of the P-90s. The jumpers were positioned to provide what cover they could, and some were cloaked, so as not to give away their full strengthjust in case. John leaned against the side of one jumper to take the weight off his foot while he waited, while Teyla and Schwartz talked quietly, and the other Athosians waited with something like a detached curiosity. They'd only ever had the expedition as an example of what Earth was like, after all, and by this point the expedition wasn't exactly representative.

McKay appeared at the last minute; he was also in his expedition jacket, and he'd found his Canada patch somewhere but stuck it to the wrong sleeve. His eyes looked clearer, though, and he didn't lean against anything when he came to stand at John's shoulder. "Somehow I don't think they're going to appreciate this kind of show of force," he said quietly.

"I don't really give a damn what they appreciate at this point," John muttered.

John expected them to land some kind of a transport ship; he'd read, once, about gliders and ha'taks and F-302s. When the burst of light filled the open space around them, every weapon went up and for a moment he thought _Wraith, Jesus, Wraith, they tricked us, they figured out how to fucking trick us_

But the light faded around humans, nice normal humans in green uniforms, who immediately put their hands in the air. "Asgard," McKay blurted a beat too late, sounding choked. "Asgard technology, notfine, it's fine, they're using Asgard beaming technology."

"What's an Asgard?" John said, lowering his stunner.

"Little green men with a hard-on for Jack O'Neill." McKay swiped his hand over his face and breathed deeply, shakily. "Christ, as if they didn't already think we've gone feral..."

The man who stepped forward from the visitors had eagles on his lapels and very little hair. "Major Sheppard?" he called cautiously. "You want to explain the warm reception?"

"Apologies, Colonel," John said. "We're all a little jumpy in this neck of the woods."

"That's understandable," Caldwell said evenly. "Let me introduce Lt. Col. Lorne, Major Leonard, Dr. Novak and Dr. Keller."

"Lt. Ford, Dr. McKay, Dr. Schwartz," John said, pointing in return, "Teyla Emmagen, Halling Kuttinen, and Marta Soleren. Their people have been our allies since we arrived in Pegasus and they took us in when we abandoned Atlantis. Orin, son of Meris, is another friend."

For a moment the two parties just regarded one another. Caldwell's crew wore flight suits and BDUs, clean and pressed, with the Earth point of origin still displayed brightly. John watched their eyes skim the crowd and the settlement beyond. Everyone wore leather and linens now, long hair and scraggly beards; the tents and lumpy cements huts streamed smoke into the chilly air as people with food lit fires to cook it. John was hyperaware of Caldwell's sharp eyes dwelling on Teyla's scars, Ford's missing eye, McKay's perpetual shakes and John's own leg that stopped at the kneeat everyone's protruding cheekbones and sunken eyes. _Refugee camp,_ they had to be thinking. _Survivors. Transients.  
_  
Sad thing was, they weren't that far off.

"It's a pleasure to finally meet all of you," Caldwell said, and even managed to sound sincere. "We've been looking for a long time."

McKay snorted. "Yes, and I'm sure you looked very, very hard."

Lorne scowled. "There's a lot of planets in Pegasus, Doctor, and you didn't exactly leave a forwarding address."

"That's _exactly_ what we did!" McKay snapped, almost shaking with sudden anger. "And while I realize the code might've been a bit too difficult for a bunch of grunts like yourselves to understand, I expected Major Carter to figure it out immediately, not _two years_ after the fact!"

Lorne and Leonard both stood very straight; Caldwell sighed. "Dr. McKay, Lieutenant Colonel Samantha Carter disappeared along with General O'Neill and the rest of SG-1 shortly after we received your final transmission. They went on a mission to retrieve a ZPM for the relief of Atlantis and never returned."

"Oh," McKay said quietly, and staggered a few steps backwards. Teyla braced him upright with one hand.

"What about the markers we left at original alpha site?" John made himself ask, instead of mentally adding to the expedition death toll. "Like McKay said, it wasn't all that obvious, but it should've lead you us."

"Major, without a ZPM it took us months to get to the Pegasus galaxy," Caldwell said bluntly. "The Wraith beat us to almost every world you listen as a potential alpha site in that last transmission. The ones that weren't scorched bare were uninhabited, and we didn't find any secret messages with our surface sweeps."

John bowed his head with a sigh. "We've been on the move for a long time," he admitted. "We...I guess we thought you'd get here faster."

"I wish we had," Caldwell said.

They stood there for a few long moments in silence before one of the doctors, slim and blonde, stepped forward and cleared her throat. "We, ah, weren't certain what you might need down here, but we brought a couple cases of MREs, some antibiotics, some diagnostic equipment, analgesics..."

"You are most generous," Teyla said smoothly, stepping away from Rodney's side. "Dr. Schwartz can assist you with the distribution of these supplies. Meanwhile, I believe the rest of us would be more comfortable continuing this discussion in the council tent."

"Of course," Caldwell said. "Major, if you could stay with Dr. Keller to help Dr. Schwartz. Lorne, Novak, with me."

John hitched his crutch under him and began to turn towards the council tent. He tried to imagine himself explaining what the expedition had enduredwho had been taken by the Wraith and who had been taken by hunger or disease or human foes, what had become of Elizabeth and Carson and Zelenka and a dozen others who should've been here, who should've survived. It seemed like more than mere words could contain, but he had a dutymultiple duties, to the dead and the missing and the people back on Earth.

Earth. Jesus. They could go back now, couldn't they?

At this point, did they even want to?

Caldwell and his people trailed a little behind John, who pretty much set the pace with his limping. McKay started to follow them but wobbled noticeably, almost staggering into a jumper. Lorne steadied him with only a slight grimace at his none-to-clean jacket. "You okay there, Doctor?"

"Yeah," McKay said quickly, "blood sugar. Um, I'm hypoglycemic and I didn'tit's just low blood sugar." He glanced at John as he spoke, almost pleading, and John decided to let it lie for the time being.

"I got a powerbar here if you want it," Lorne said, fishing in his pocket. A couple of the Marines couldn't avoid staring; somehow the silvery wrapper seemed to be a more tangible sign of home than anything else so far, and the prospect of something more substantial than boiled tava beans had several stomachs growling audibly.

McKay stared, too, with big pathetic calf-eyes. "What kind is it?" he asked, a little hopefully.

"Um..." Lorne glanced self-consciously at the audience he'd attracted, then checked the wrapper warily, as if he feared being jumped. Feral, indeed. "Peanut butter?"

McKay's face fell. "Sorry, never mind," he stammered, and trudged across the frosted grass to the council tent, shoulders hunched. "I'm allergic to peanuts."


End file.
